march action
grpc RPC:
1、grpc stub
2、grpc skeleton
Language Guide
https://developers.google.com/protocol-buffers/docs/proto?hl=zh-cn
Language Guide (proto3)
https://developers.google.com/protocol-buffers/docs/proto3?hl=zh-cn
Protocol Buffers Version 3 Language Specification
https://developers.google.com/protocol-buffers/docs/reference/proto3-spec